Abstract: Does Richard Posner lead a double life as scholar and judge? Posner’s prodigious and prolific scholarship, developing and applying the functionalist, rational approach (he might call it economic or pragmatic) in virtually every field of law, ranks him among the greatest legal thinkers. It also places him at the forefront of the revolutionary assault on the formalist establishment’s continuing dominance of the teaching, and therefore the practice, of law. Indeed, scholarly Posner seems to relish the role of provocateur; witness his recent contribution in these pages skewering the pontiffs of constitutional law. But what of Judge Posner, now marking his twenty-fifth year on the Court of Appeals for the Seventh Circuit? In that time he has served a lengthy term as Chief Judge and authored volumes of opinions. Besides wondering how he does it all, I want to know how Posner squares the role of judge with that of scholar provocateur. Is he a judicial Clark Kent, passing himself off as a mild-mannered, droll, keen-witted judge, wearing glasses and a black robe as a disguise, only to throw them off to write seditious tracts and save the world? Some clues may be found in Indiana Harbor Belt Railroad Co. v. American Cyanamid Co., a Posner opinion that has become a basic staple of torts courses on the preeminent question of when it is better to use negligence or strict liability. After commenting on the importance as well as the problematics of this opinion, I surmise what he might actually be up to — all in tribute to the judicial Posner.